OP is right, this is clearly discriminatory for a part of the players based on their location, meaning that people who live outside the selected area do not benefit of equal treatment or equality of chances.
While the vitality maintaining rune is, indeed, a reward for an action (participanting in beta testing of L2M), some players have the option to choose between performing that action and obtaining the reward or just giving it up, while others do not have the option the perform the action. The distinction between the two categories is made simply by their physical location.
This doesn't mean that all players from countries outside the beta list should automatically be given the rune, but it does mean that they should be given the oportunity to perform an action rewarded with that rune, if they choose to.